The Chinese were reportedly spotted mining in the river at Asendua near Hiawa in the Amenfi Central District.
The Chinese nationals, identified as 41-year-old Tan Zhonguang, 40-year-old Wei Wenzxue, 54-year-old Li Shiping and 35-year-old Wei Hue Lim were apprehended on the site together with their Ghanaian counterpart, 44-year-old Kwabena Acheampong.
The patrol team impounded an excavator with chassis number SYO33DBG52838 at the site.
The team also seized one locally-manufactured single-barreled gun with three ammunitions and destroyed two water-pumping machines.
The suspects and the exhibits have been handed over to the Manso Central Police station pending further investigations.
Operation Vanguard in a statement said it "is focused on its mandate of flushing out illegal mining and we are grateful to the general public for the support.
"The JTF calls for more support by way of information on where illegal miners are operating.
"Let us all fight this canker together to achieve the aim of keeping our environment safe for today and in the future.
Some of the residents also pointed out that the unannounced swoop was embarked upon following a tip-off the police received from an informant.